Lighting devices using a fluorescent tube as a light source have conventionally been known, and such lighting devices are used as backlight units for display devices such as liquid crystal display devices (see, for example, Patent Document 1).
FIG. 13 is a diagram schematically showing an example of the structure of a conventional liquid crystal display device. A description will be given below of the structure of a conventional liquid crystal display device with reference to FIG. 13.
In the conventional liquid crystal display device, as shown in FIG. 13, a backlight unit 120 is placed at the rear surface side of a liquid crystal display panel 110. And the conventional liquid crystal display device is structured such that images are displayed on the display surface (the front surface) of the liquid crystal display panel 110 by irradiating the rear surface of the liquid crystal display panel 110 with light emitted from the backlight unit 120.
The backlight unit 120 is at least provided with a metal backlight chassis 101, fluorescent tubes 102 housed in the backlight chassis 101, a reflection sheet 103 reflecting light from the fluorescent tubes 102, and an optical sheet 104 that, for example, diffuses light from the fluorescent tubes 102. The reflection sheet 103 is disposed along the housing-area-side surface of the backlight chassis 101, and the optical sheet 104 is disposed so as to cover the housing area of the backlight chassis 101 from the front side. The optical sheet 104 is also supported by a support member 105 installed on a bottom section 101a of the backlight chassis 101.
The support member 105 includes a support prop 105a for supporting the optical sheet 104 and an engagement piece 105b that engages with the bottom section 101a of the backlight chassis 101. And, the support member 105 is installed on the bottom section 101a of the backlight chassis 101 by engaging the engagement piece 105b of the support member 105 with the bottom section 101a of the backlight chassis 101. Incidentally, in the state in which the support section 105 is installed on the bottom section 101a of the backlight chassis 101, the engagement piece 105b of the support member 105 projects rearward from the bottom section 101a of the backlight chassis 101.
In the backlight unit 120 as described above, a power supply substrate 106 is typically placed behind the backlight chassis 101 for supplying power to the fluorescent tubes 102. In this case, for electrically insulating the backlight chassis 101 and the power supply substrate 106 from each other, an insulation sheet 107 is disposed between the backlight chassis 101 and the power supply substrate 106, and also, the insulation sheet 107 is bonded to the bottom section 101a of the backlight chassis 101.
Patent Document 1: JP-A-2007-157451